Differential Input Patents (Class 327/65)
-
Patent number: 8896289Abstract: A circuit includes an input stage, a comparison stage, and a calibration stage. The input stage is configured to receive a first input signal, to generate a first reference signal, and to generate a second reference signal. The comparison stage is configured to generate a first comparison output signal in response to the first reference signal and a third reference signal and to generate a second comparison output signal in response to the second reference signal and a fourth reference signal. The calibration stage is configured to generate a detection signal responsive to the presence of the first comparison output signal and the second comparison output signal having a signal frequency within a predetermined frequency band.Type: GrantFiled: May 18, 2012Date of Patent: November 25, 2014Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.Inventor: Wei Chih Chen
-
Patent number: 8884655Abstract: Differential voltage mode signal driver circuitry is presented in which a differential current mode amplifier input stage provides a differential signal, and an output stage includes a pair of bipolar transistors receiving the differential signal and being connected in series with a pair of cross-coupled field effect transistors that are coupled to corresponding current sources, where a negative impedance circuit is connected between the field effect transistors to substantially cancel a parasitic capacitance of a driven output circuit.Type: GrantFiled: April 11, 2013Date of Patent: November 11, 2014Assignee: Texas Instruments IncorporatedInventors: Tonmoy Shankar Mukherjee, Arlo Jame Aude
-
Patent number: 8878570Abstract: An integrated circuit includes a configurable interface. The configurable interface includes an operational amplifier, a programmable gain amplifier, an analog-to-digital converter and a first select circuit. The first select circuit is configured to selectively couple the operational amplifier to the analog-to-digital converter in response to a first control signal. The first select circuit is further configured to selectively couple the programmable gain amplifier to the analog-to-digital converter in response to the first control signal.Type: GrantFiled: September 30, 2011Date of Patent: November 4, 2014Assignee: Silicon Laboratories Inc.Inventor: Axel Thomsen
-
Patent number: 8866531Abstract: Broadband analog radio-frequency devices can be used to create building blocks for scalable analog signal processors that operate over bandwidths of 50 MHz to 20 GHz or more. Example devices include integrators (transconductors), digitally controlled attenuators, buffers, and scalable summers implemented using deep sub-micron CMOS technology. Because the devices are implemented in CMOS, the ratio of trace/component size to signal wavelength is about the same as that of low-frequency devices implemented in printed circuit boards. Combining this scaling with high gain/high bandwidth enables implementation of feedback and programmability for broadband analog signal processing.Type: GrantFiled: February 11, 2011Date of Patent: October 21, 2014Assignee: Newlans, Inc.Inventors: Dev V. Gupta, Zhiguo Lai
-
Patent number: 8841961Abstract: An apparatus includes a processor and a device. The processor generates an output signal and a control signal. The device consumes power while operating in first and second states. The device consumes less power while in the first state than while in the second state. The processor: accounts for a transition time for the device to transition among a powered off state, the first state, and the second state; and generates the control signal based on the transition time. The device: in response to the control signal, transitions to the second state at a speed of periodicity of a periodic signal of the processor; subsequent to the transitioning to the second state, performs a function based on the output signal; and subsequent to performing the function, transitions from the second state to either the first state or the powered off state.Type: GrantFiled: November 4, 2013Date of Patent: September 23, 2014Assignee: Marvell World Trade Ltd.Inventor: Sasan Cyrusian
-
Patent number: 8836376Abstract: A comparator includes: a differential amplifier of which operational state is switched in response to a clock-signal, and which outputs a first intermediate-output corresponding to a first input-signal and a second intermediate-output corresponding to a second input-signal; a differential latch circuit of which operational state is switched in response to the clock-signal, and a state of which is changed depending on the first intermediate-output and the second intermediate-output; a first adjuster configured to adjust a threshold of the differential latch circuit with respect to a change of a state of the first intermediate-output and a change of a state of the second intermediate-output; and a second adjuster configured to adjust a threshold variation of the differential latch circuit with respect to a change of a state of the first intermediate-output and a change of a state of the second intermediate-output.Type: GrantFiled: August 28, 2013Date of Patent: September 16, 2014Assignee: Fujitsu LimitedInventor: Takumi Danjo
-
Patent number: 8836375Abstract: A comparator apparatus includes an amplifier and one or more latched comparators connected to the amplifier that compares input voltage signals to predefined reference voltage signals. The comparator apparatus includes an offset that limits the minimum input differential voltage signal with respect to the predefined voltage signals. A calibration component is electrically connected to the latched comparator and assists in continuously measuring and compensating the offset.Type: GrantFiled: September 6, 2012Date of Patent: September 16, 2014Assignee: LSI CorporationInventor: Kalyan Brata Ghatak
-
Patent number: 8829942Abstract: A comparator is provided and the comparator includes a comparing input unit and a latching unit. Wherein, the comparing input unit has a first input receiving a first comparing signal and has a second input receiving a second comparing signal. The comparing input unit drives a first intermediate node signal at a first intermediate node depending on the first comparing signal according to a first strobe signal, and the comparing input unit drives a second intermediate node signal at a second intermediate node depending on the second comparing signal according to the first strobe signal. The latching unit determines a comparing result according to at least one of the first intermediate node signal and the second intermediate node signal. In addition, the latching unit latches the comparing result according to a second strobe signal.Type: GrantFiled: November 13, 2012Date of Patent: September 9, 2014Assignee: University of MacauInventors: Chi-Hang Chan, Yan Zhu, U-Fat Chio, Sai-Weng Sin, Seng-Pan U, Rui Paulo da Silva Martins
-
Patent number: 8829941Abstract: A method is provided for receiving a differential signal pair input at a first circuit stage and converting the differential signal pair input to a single-ended signal at a second circuit stage. The method also provides for receiving an output of the first circuit stage and an output of the second stage at a third circuit stage and transmitting an amplified signal output from the third circuit stage. The method allows for a 60 dB signal gain or more. A circuit is also provided that includes multiple circuit stages that can provide signal gain to an input differential signal pair. The circuit converts the differential pair into a single-ended signal and transmits the amplified signal as an output. The circuit provides the signal gain without using a current mirror. A computer readable storage device encoded with data for adapting a manufacturing facility to create an apparatus is also provided.Type: GrantFiled: December 10, 2011Date of Patent: September 9, 2014Assignee: Advanced Micro Devices, Inc.Inventors: Xin Liu, Arvind Bomdica, Yikai Liang
-
Patent number: 8829943Abstract: An analog disconnection envelope detection circuit having a low power supply detects a high speed, high differential voltage disconnect state on a data line. Level-shifting circuitry shifts the voltage level of two input signals by the value of a detection threshold voltage, generates differential signals used to indicate conditions of the input signals, and mitigates effects of input differential signal common-mode voltage on the detection operation. Circuitry is provided to equalize VDS of detecting tail current sources, thereby eliminating errors resulting from VDS mismatch of tail current sources. Comparator circuitry compares the sets of differential signals and indicates when the absolute difference between the two input signals is greater than a reference voltage. Output circuitry generates a disconnect signal corresponding to the disconnect condition.Type: GrantFiled: October 19, 2012Date of Patent: September 9, 2014Assignee: STMicroelectronics International N.V.Inventor: Daljeet Kumar
-
Patent number: 8810282Abstract: Apparatus and methods for voltage comparison are provided. In one embodiment, a comparator includes a first input transistor having a gate configured to receive a first input voltage and a second input transistor having a gate configured to receive a second input voltage. The first and second input transistors can be used to compare the first input voltage to the second input voltage. Additionally, the comparator further includes a first Miller capacitor electrically connected to a drain of the first input transistor and a second Miller capacitor electrically connected to a drain of the second input transistor. Furthermore, first and second inverting amplification circuits are electrically connected across the first and second Miller capacitors, respectively, so as to increase the effective capacitance of the capacitors. The first and second Miller capacitors can be used to extend the comparator's integration time, thereby enhancing the performance of the comparator.Type: GrantFiled: December 21, 2012Date of Patent: August 19, 2014Assignee: Analog Devices Inc.Inventor: Hongxing Li
-
Patent number: 8803557Abstract: A comparator circuit includes a first comparator configured to store an offset during a first period, and to compare first and second input signals while compensating for the stored offset to generate a first comparison signal during a second period, a second comparator configured to compare the first and second input signals while compensating for an offset to generate a second comparison signal, and a compensation amount controller configured to control an offset compensation amount of the second comparator when the first and second comparison signals have different values.Type: GrantFiled: March 16, 2013Date of Patent: August 12, 2014Assignee: SK Hynix Inc.Inventor: Ki-Han Kim
-
Patent number: 8791691Abstract: A signal detector includes a summation unit connected to offset first and second input signals representing a differential input signal into two offset pairs of first and second signals. The signal detector also includes a detection unit connected to select the first signal from one of the offset pairs of first and second signals and the second signal from the other of the offset pairs in an overlap portion of the first and second signals to form a complementary pair of overlap signals and provide a differentially peak-detected output signal from the complementary pair of overlap signals. Additionally, the signal detector includes a comparator connected to provide a detection output signal corresponding to the differentially peak-detected output signal and a reference signal. A method of operating a signal detector is also included.Type: GrantFiled: March 24, 2011Date of Patent: July 29, 2014Assignee: LSI CorporationInventor: Zichuan Cheng
-
Patent number: 8779801Abstract: A switching circuit includes a first input stage having an input for receiving a first input signal, an output, and a power terminal for receiving an increasing analog current, a second input stage having an input for receiving a second input signal, an output, and a power terminal for receiving a decreasing analog current, and an output node coupled to the outputs of the first input stage and the second input stage for providing a switched output signal. An output stage is coupled between the first and second input stages and the output node. The first and second input stages are operational amplifiers.Type: GrantFiled: December 3, 2012Date of Patent: July 15, 2014Assignee: STMicroelectronics (Shenzhen) R&D Co. Ltd.Inventors: Min Chen, Wen Liu, HongXia Li, XiaoWu Dai
-
Patent number: 8780649Abstract: A buffer and control circuit for a synchronous memory controller includes first and second differential comparators and control logic. The first differential comparator is provided with positive and negative differential input signals and the second differential comparator is provided with offset positive and negative differential input signals. The first and second differential comparators generate output signals based on magnitudes of the positive and negative differential input signals and the offset positive and negative differential input signals. The control logic generates a reference strobe signal based on the output signals.Type: GrantFiled: April 26, 2012Date of Patent: July 15, 2014Assignee: Freescale Semiconductor, Inc.Inventors: Nitin Pant, Trong D. Nguyen, Samaksh Sinha
-
Patent number: 8773174Abstract: A rail to rail differential buffer input stage includes n-type and p-type input differential transistor pairs connected in voltage follower configuration to the power supply rails. A reference voltage generator includes a reference differential transistor pair generating a dynamic reference voltage relative to the common mode input voltage. Dummy n-type and p-type transistor pairs have current conducting paths connected in parallel with the input differential pairs and are controlled by the dynamic reference voltage to divert supply rail current away from and deactivate one of the associated input differential pairs when the common mode input voltage is further from the dynamic reference voltage than a threshold value. Both the dummy pairs conduct and both the input differential pairs are activated when the common mode input voltage is closer to the dynamic reference voltage VB than the threshold value so that the overall transconductance of the buffer input stage remains constant.Type: GrantFiled: December 16, 2012Date of Patent: July 8, 2014Assignee: Freescale Semiconductor, Inc.Inventors: Yang Wang, Jianzhou Wu, Xiuqiang Xu, Yizhong Zhang
-
Patent number: 8773169Abstract: A high frequency input signal comparator for optimizing group delay, reducing input frequency dependent offset and an offset auto-zeroing latch core are described. The comparator may include an isolation switch stage, and a latch core. The isolation switch stage may isolate latch core depending upon a control signal, thereby reducing input frequency dependent offset. The latch core may include a pair of inverters cross coupled via an impedance to one another. The latch core may include latch switches selected to attain a certain gain across the individual inverters comprising the latch core while resetting the latch core. The gain across the individual inverters during the acquire/reset phase may bootstrap the coupling impedances, thereby reducing loading and group delay at the input of the latch core. The coupling impedances may be designed to minimize or auto-zero statistical offset, thereby minimize input referred offset.Type: GrantFiled: October 22, 2010Date of Patent: July 8, 2014Assignee: Analog Devices, Inc.Inventors: Huseyin Dinc, Michael Elliot, William Thomas Boles
-
Patent number: 8767841Abstract: Techniques for de-modulating a high-supply-domain differential signal and a common-mode clock in a front-end receiver are described herein. In one embodiment, a method for receiving a signal comprises receiving the signal via a receiver input, the received signal comprising a differential signal and a common-mode clock signal. The method also comprises shifting the received signal from a first voltage range to a second voltage range that is lower than the first voltage range, and providing the shifted received signal on a first level-shifted signal line and a second level-shifted signal line. The method further comprises sensing voltage differences between the first and second level-shifted lines to recover the differential signal, and sensing common-mode voltages on the first and second level-shifted signal lines to recover the common-mode clock signal.Type: GrantFiled: March 4, 2013Date of Patent: July 1, 2014Assignee: QUALCOMM IncorporatedInventors: Miao Li, Xiaohua Kong, Yan Hu, Zhi Zhu
-
Patent number: 8760196Abstract: A circuit for detecting out-of-band signals is disclosed. In one embodiment, the circuit includes a first differential circuit configured to level shift and positively rectify a differential input signal to produce a first output component of a differential output signal. The detector further includes a second differential circuit configured to level shift and negatively rectify the differential input signal to produce a second output component of the differential output signal. A third differential circuit is configured to level shift and output first and second fixed voltages based on an input reference voltage and a ground voltage. The circuit is configured to provide the differential output signal and the first and second fixed voltages to an indicator circuit configured to assert an indication responsive to detecting that a differential voltage of the differential output signal is greater than a differential voltage of the first and second fixed voltages.Type: GrantFiled: December 12, 2011Date of Patent: June 24, 2014Assignee: Advanced Micro DevicesInventors: Xin Liu, Arvind Bomdica
-
Patent number: 8742964Abstract: An apparatus includes a capacitance-to-voltage converter circuit configured to be electrically coupled to a micro-electromechanical system (MEMS) sensor circuit. The capacitance-to-voltage converter circuit includes a differential chopping circuit path configured to receive a differential MEMS sensor output signal and invert a polarity of the differential chopping circuit path, and a differential sigma-delta analog to digital converter (ADC) circuit configured to sample the differential MEMS sensor output signal and provide a digital signal representative of a change in capacitance of the MEMS sensor.Type: GrantFiled: January 16, 2013Date of Patent: June 3, 2014Assignee: Fairchild Semiconductor CorporationInventors: Jonathan Adam Kleks, Ion Opris, Justin Seng
-
Patent number: 8737456Abstract: Methods and apparatus are disclosed, such as those involving mixed-mode signaling that includes transmitting a differential signal and a common mode signals over the same pair of interconnect traces. One such apparatus includes a first transmitter configured to transmit a differential signal through a pair of electrically conductive lines in a first direction. The differential signal has a first frequency and carries electronic data. The apparatus further includes a second transmitter configured to transmit a common mode signal through the pair of electrically conductive lines in the first direction. The common mode signal is superimposed onto each of the differential signal. The common mode signal has a second frequency that is lower than the first frequency and carries a control signal. This configuration reduces the number of lines and pins on electronic circuits, thereby saving space thereon.Type: GrantFiled: January 17, 2013Date of Patent: May 27, 2014Assignee: Micron Technology, Inc.Inventor: Timothy M. Hollis
-
Patent number: 8704553Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits and embodiments such as operational transconductance amplifiers, biasing circuits, integrators, continuous-time sigma delta modulators, track-and-bold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.Type: GrantFiled: October 2, 2012Date of Patent: April 22, 2014Assignee: The Trustees of Columbia University in the City of New YorkInventors: Kong-Pang Pun, Shouri Chatterjee, Peter R. Kinget
-
Patent number: 8705637Abstract: A signal transmission device including: a differential signal transmission unit having two output terminals for outputting a differential signal to a paired signal lines including first and second signal lines; a single-ended signal transmission unit having two output terminals for outputting independent two-channel single-ended signals to the paired signal lines; and a filter unit having first and second common mode filters. One terminal of the differential signal transmission unit and one terminal of the single-ended signal transmission unit are connected to the first signal line via one inductor of the first common mode filter of the filter unit. The other one terminal of the differential signal transmission unit and the other one terminal of the single-ended signal transmission unit are connected to the second signal line via one inductor of the second common mode filter of the filter unit.Type: GrantFiled: February 13, 2012Date of Patent: April 22, 2014Assignee: Panasonic CorporationInventors: Osamu Shibata, Hiroshi Suenaga
-
Patent number: 8692583Abstract: An apparatus, system, and method are provided for a differential integrated input circuit. The apparatus includes n-type semiconductor devices and p-type semiconductor devices. The p-type semiconductor devices are cross-coupled with the n-type semiconductor devices. Each of the p-type semiconductor devices biases a corresponding n-type semiconductor device.Type: GrantFiled: August 26, 2011Date of Patent: April 8, 2014Assignee: NXP B.V.Inventors: Aloysius Johannes Maria Boomkamp, Stefan Butselaar, Ben Gelissen, Mehdi El Ghorba, Cornelis Klaas Waardenburg
-
Patent number: 8692582Abstract: Integrated circuits having analog-to-digital converters are provided. Analog-to-digital converters may contain latched comparators. A latched comparator may include inputs configured to receive a differential input voltage signal, a differential reference voltage signal, and a clock signal. The comparator may include a preamplifier, a latching circuit, a level shifter, and a flip-flop coupled in series. The preamplifier may include large input transistors for minimizing offset, stacked tail transistors, and diode-connected load transistors for minimizing kickback noise. The preamplifier may be used to generate amplified voltage signals. The latching circuit may include a first pair of cross-coupled pull-down transistors, a second pair of cross-coupled pull-up transistors, and precharge transistors.Type: GrantFiled: January 6, 2012Date of Patent: April 8, 2014Assignee: Altera CorporationInventors: Ali Atesoglu, Weiqi Ding
-
Patent number: 8686757Abstract: An apparatus and a method are provided for selectively enabling and disabling a squelch circuit in a Serial Advanced Technology Attachment (SATA) host or SATA device while maintaining proper operation of the host and device. An apparatus and method are provided which allow the squelch circuit to be selectively enabled and disabled across SATA power states (PHY Ready, Partial, and Slumber) and in Advanced Host Controller Interface (AHCI) Listen mode.Type: GrantFiled: March 19, 2012Date of Patent: April 1, 2014Assignee: Intel CorporationInventors: Jien-Hau Ng, Tea M. Lee
-
Patent number: 8669788Abstract: The present document relates to a method and system for determining the voltage level of an input signal compared to a reference voltage, providing a plurality of level indications regarding an input voltage with respect to a reference voltage. The multi-level comparator comprises an input stage converting the input voltage into a first current and converting the reference voltage into a second current; and a plurality of comparator stages, each comprising a first current amplification unit amplifying the first current with a first gain, a second current amplification unit amplifying the second current with a second gain, and an output port providing an indication whether the first comparator current is smaller or larger than the second comparator current; wherein respective ratios of the first gain and the second gain of the plurality of comparator stages are different.Type: GrantFiled: June 28, 2012Date of Patent: March 11, 2014Assignee: Dialog Semiconductor GmbHInventor: Horst Knoedgen
-
Patent number: 8653859Abstract: An electronic circuit includes a differential input section, a current mirror section, an operational amplifier, an inverter, and a compensation voltage generator. The differential input section and the current mirror section are coupled together, forming a first common drain node and a second common drain node. The current mirror section has two p-type transistors coupled together at a common gate node. The operational amplifier has a positive input coupled to the first common drain node, a negative input coupled to the compensation voltage generator, and an output coupled to the common gate node. The inverter has an input node coupled to the second common drain node. The compensation voltage generator provides a compensation voltage to replicate a switching threshold voltage of the inverter.Type: GrantFiled: July 27, 2011Date of Patent: February 18, 2014Assignee: Advanced Micro Devices, Inc.Inventor: Stephen F. Greenwood
-
Patent number: 8648623Abstract: A single stage current sense amplifier is described that generates a differential output that is proportional to a current through a sense resistor. The voltage across the sense resistor is Vsense. The current sense amplifier includes a differential transconductance amplifier having high impedance input terminals. An on-chip RC filter filters transients in the Vsense signal. A feedback circuit for each leg of the amplifier causes a pair of input transistors to conduct a fixed constant current irrespective of Vsense, which stabilizes the transconductance. A gain control resistor (Re) is coupled across terminals of the pair of input transistors and has Vsense across it. The current through the gain control resistor is therefore Vsensex1/Re. A level shifting circuit coupled to each of the input transistors lowers a common mode voltage at an output of the amplifier. Chopper circuits at the input and output cancel any offset voltages.Type: GrantFiled: April 16, 2012Date of Patent: February 11, 2014Inventors: Hengsheng Liu, Edson Wayne Porter, Gregory Jon Manlove
-
Patent number: 8638126Abstract: The present invention discloses a rail-to-rail comparator. The rail-to-rail comparator includes: a positive voltage rail providing a positive supply voltage, a ground voltage rail providing a ground voltage, an input stage, and an output stage. The input stage includes: a positive and a negative input terminals for receiving a first input signal and a second input signal; a first differential amplifier circuit, which includes a pair of depletion NMOS transistors to generate a first pair of differential currents; and a second differential amplifier circuit, which includes a pair of native NMOS transistors to generate a second pair of differential currents. The output stage is coupled to the first differential amplifier circuit and the second differential amplifier circuit, and generates an output signal related to a difference between the first input signal and the second input signal.Type: GrantFiled: January 18, 2012Date of Patent: January 28, 2014Assignee: Richtek Technology Corporation, R.O.C.Inventors: Chieh-Min Lo, Tzu-Huan Chiu, Chien-Sheng Chen, Chien-Ping Lu
-
Patent number: 8638125Abstract: A low voltage differential signal (LVDS) driver circuit with reduced power consumption. A pre-driver stage, implemented as a differential current mode amplifier, is driven by the differential input signal and provides a corresponding differential drive signal, which drives the output stage, implemented as a differential voltage mode amplifier, which, in turn, provides the differential output signal for the load. Total current consumption equals the load current, which is provided by the output stage, plus a much smaller current used by the pre-driver stage.Type: GrantFiled: June 14, 2011Date of Patent: January 28, 2014Assignee: Texas Instruments IncorporatedInventors: Khaldoon Abugharbieh, Jitendra Mohan, Ivan Duzevik
-
Patent number: 8638127Abstract: Embodiments related to an undervoltage detector are described and depicted. An undervoltage detector is formed to detect a low input bias voltage with a voltage divider network including first and second series circuits of semiconductor devices coupled to terminals of the input bias voltage source, and a resistor voltage divider including first and second voltage divider resistors coupled in series with the first and second series circuits. A ratio representing the numbers of semiconductor devices in the series circuits is substantially equal to a ratio of resistances in the resistor voltage divider. The equality of the ratios may be corrected by the presence of other resistances in the undervoltage detector. The semiconductor devices are each coupled in a diode configuration. The first series circuit is coupled to a current mirror to provide a bias current for a comparator that produces an output signal for the undervoltage detector.Type: GrantFiled: November 29, 2010Date of Patent: January 28, 2014Assignee: STMicroelectronics (Shenzhen) R&D Co., LtdInventors: Ni Zeng, Da Song Lin
-
Patent number: 8625683Abstract: A serial data transmission system, includes a transmitting terminal for transmitting a data, a receiving terminal for receiving the data transmitted by the transmitting terminal, a first connecting capacitor connected between the transmitting terminal and the receiving terminal, and a second connecting capacitor connected between the transmitting terminal and the receiving terminal, wherein the transmitting terminal comprises a transmitting terminal driver unit and an amplitude detection unit connected with the transmitting terminal driver unit, the transmitting terminal driver unit outputs a pair of differential signals, the amplitude detection unit detects an amplitude variation of the differential signals output by the transmitting terminal driver unit, and outputs an indication signal indicating whether the transmitting terminal and the receiving terminal are properly connected with each other. A serial data transmission method is further provided.Type: GrantFiled: May 17, 2012Date of Patent: January 7, 2014Assignee: IPGoal Microelectronics (SiChuan) Co., Ltd.Inventors: Zhaolei Wu, Lei Li
-
Patent number: 8610466Abstract: A high-speed differential comparator circuit is provided with an accurately adjustable threshold voltage. Differential reference voltage signals are provided to control the threshold voltage of the comparator. The common mode voltage of the reference signals preferably tracks the common mode voltage of the differential high-speed serial data signal being processed by the comparator circuit.Type: GrantFiled: July 2, 2012Date of Patent: December 17, 2013Assignee: Altera CorporationInventors: Weiqi Ding, Mingde Pan
-
Patent number: 8604838Abstract: An apparatus for comparing differential input signal inputs is provided. The apparatus comprises a CMOS sense amplifier (which has having a first input terminal, a second input terminal, a first output terminal, and a second output terminal), a first output circuit (which has a first load capacitance), a second output circuit (which has a second load capacitance), and an isolation circuit. The isolation circuit is coupled between the first output terminal of the CMOS sense amplifier and the first output circuit and is coupled between the second output terminal of the CMOS sense amplifier and the second output terminal of the CMOS sense amplifier. The isolation circuit isolates the first and second load capacitances from the CMOS sense amplifier.Type: GrantFiled: December 12, 2011Date of Patent: December 10, 2013Assignee: Texas Instruments IncorporatedInventor: Robert F. Payne
-
Patent number: 8598913Abstract: This document discusses, among other things, apparatus and methods for controlling a hysteresis range of a voltage comparator. In an example, an apparatus can include an amplifier having a temperature dependency, a comparator configured to receive first and second currents and to provide an output voltage indicative of a hysteretic comparison of the first and second input voltages, wherein a range of hysteresis of the apparatus is controlled over a range of temperatures. In an example, the amplifier can be configured to receive first and second input voltages and to provide the first and second currents.Type: GrantFiled: November 22, 2011Date of Patent: December 3, 2013Assignee: Fairchild Semiconductor CorporationInventors: Tyler Daigle, Andrew M. Jordan
-
Patent number: 8581632Abstract: A comparator is provided. The comparator includes a voltage generator, a buffer unit and a threshold control loop. The voltage generator has an output terminal for providing a reference voltage according to a constant current. The buffer unit provides an output signal according to a first input signal and a bias signal. The threshold control loop provides the bias signal to the buffer unit according to a second input signal, so as to regulate a transition threshold of the buffer unit to close to the second input signal. The output signal represents a compare result of the first and second input signals. The buffer unit and the threshold control loop are powered by the reference voltage.Type: GrantFiled: September 12, 2012Date of Patent: November 12, 2013Assignee: Mediatek Inc.Inventor: Keng-Jan Hsiao
-
Patent number: 8575969Abstract: A semiconductor device configured that its differential pair is made operable in both states of high speed with a high consumption current and low speed with a low consumption current. A differential circuit includes differential pair transistors and a tail current source for supplying a tail current that is switchable so that an amount of current flowing in the differential pair transistors may be switched between at least two sates of different levels. The differential pair transistors have a characteristic that, with a decrease of currents flowing in the differential pair transistors, a value of ?(?I/gm) decreases monotonously, where ? denotes a standard deviation, ?I denotes a difference of the amounts of current of the differential pair transistors, and gm denotes transconductance of the differential pair transistors.Type: GrantFiled: May 29, 2012Date of Patent: November 5, 2013Assignee: Renesas Electronics CorporationInventor: Kiyohiko Sakakibara
-
Patent number: 8575968Abstract: A circuit method includes periodically increasing a tail current of a differential stage of a comparator to periodically power on the differential stage to a power-on state, and periodically decreasing the tail current of the differential stage to periodically power down the differential stage to a low-power state. The periodically increasing of the tail current and the periodically decreasing of the tail current are asynchronous operations for powering on the differential stage to the power-on state and powering down the differential stage to the low-power state. Periodically increasing the tail current and the periodically decreasing the tail current asynchronously for powering on the differential stage to the power-on state and powering down the differential stage to the low-power state provide for low noise and high speed during signal comparison.Type: GrantFiled: December 12, 2011Date of Patent: November 5, 2013Assignee: Marvell World Trade Ltd.Inventor: Sasan Cyrusian
-
Publication number: 20130286751Abstract: A buffer and control circuit for a synchronous memory controller includes first and second differential comparators and control logic. The first differential comparator is provided with positive and negative differential input signals and the second differential comparator is provided with offset positive and negative differential input signals. The first and second differential comparators generate output signals based on magnitudes of the positive and negative differential input signals and the offset positive and negative differential input signals. The control logic generates a reference strobe signal based on the output signals.Type: ApplicationFiled: April 26, 2012Publication date: October 31, 2013Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Nitin Pant, Trong D. Nguyen, Samaksh Sinha
-
Patent number: 8570072Abstract: A comparator circuit for providing hysteresis comprises first and second differentially coupled transistors. The first of the differentially coupled transistors provides drain current to first and second load transistors. The second of the differentially coupled transistors provides drain current to third and fourth load transistors. In one example embodiment, the drain of the first of the differentially coupled transistors also drives the gate of the first and third load transistors, while the drain of the second of the differentially coupled transistors drives the gate of the second and fourth transistors.Type: GrantFiled: November 2, 2010Date of Patent: October 29, 2013Assignee: Marvell International Ltd.Inventors: David Gozali, Hong Liang Zhang
-
Publication number: 20130278291Abstract: A circuit includes a load; a first differential pair coupled to the load and responsive to input data; a second differential pair coupled to the load and responsive to the input data; a third differential pair coupled to the first differential pair and the second differential pair and responsive to a first control signal and a second control signal; a bias circuit configured to pull a node coupled to both the first differential pair and the second differential pair to a predetermined state; and a current source coupled to the third differential pair and the bias circuit.Type: ApplicationFiled: June 19, 2013Publication date: October 24, 2013Inventors: John F. STOOPS, Daniel G. KNIERIM
-
Patent number: 8542035Abstract: A squelch detection circuit for high-speed serial communication includes: an input level shifter configured to receive signals inputted through signal lines and shift the received signals to a predetermined potential level; a comparator configured to receive signals outputted from the input level shifter, and compares the received signals to determine whether data signals are noise or signal components; and a reset signal generator configured to receive the signals outputted from the input level shifter, convert the received signals into a single signal, and then generate a reset signal for an elastic buffer. The squelch detection circuit may detect a squelch state and provide a reset value for an elastic buffer in a USB 2.0 interface, and may reduce power consumption as much as possible in a suspend mode.Type: GrantFiled: December 15, 2010Date of Patent: September 24, 2013Assignee: Postech Academy-Industry FoundationInventors: Hong June Park, Seong Hwan Jeon
-
Publication number: 20130241599Abstract: A comparator has a first terminal, a second terminal, and an output terminal. A selection circuit is coupled to the first terminal. A calibration circuit is coupled to the output terminal and the second terminal. The comparator is configured to operate in a first mode when the selection circuit provides a first input signal to the first terminal and the calibration circuit provides a second input signal to the second terminal. The comparator is configured to operate in a second mode when the selection circuit provides a first calibration signal to the first terminal and the calibration circuit provides a second calibration signal to the second terminal based on an output signal at the output terminal. The comparator generates the output signal based on the first calibration signal and the second calibration signal.Type: ApplicationFiled: March 14, 2013Publication date: September 19, 2013Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.Inventor: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
-
Patent number: 8531209Abstract: A circuit includes a load; a first differential pair coupled to the load and responsive to input data; a second differential pair coupled to the load and responsive to the input data; a third differential pair coupled to the first differential pair and the second differential pair and responsive to a first control signal and a second control signal; a bias circuit configured to pull a node coupled to both the first differential pair and the second differential pair to a predetermined state; and a current source coupled to the third differential pair and the bias circuit.Type: GrantFiled: January 16, 2009Date of Patent: September 10, 2013Assignee: Tektronix, Inc.Inventors: John F. Stoops, Daniel G. Knierim
-
Patent number: 8526905Abstract: In accordance with embodiments of the present disclosure, a merged filter-transconductor-upconverter for use in a wireless communication device is provided.Type: GrantFiled: September 22, 2010Date of Patent: September 3, 2013Assignee: Intel IP CorporationInventors: Omid Oliaei, Julian Aschieri
-
Patent number: 8519753Abstract: Here, an apparatus is provided. The apparatus comprises a first supply rail, a second supply rail, a first ambipolar transistor (which is coupled to the first supply rail at its drain and which receives a reference voltage at its gate), a second ambipolar transistor (which is coupled to the first supply rail at its drain and which receives an input signal at its gate), a current source (which is coupled between the sources of the first and second ambipolar transistors and the second supply rail), and an output circuit (which is coupled to drain of the first ambipolar transistor). In operation, the output circuit provides an output signal having a frequency that is about twice the frequency of the input signal.Type: GrantFiled: December 13, 2010Date of Patent: August 27, 2013Assignee: Texas Instruments IncorporatedInventor: Andrew Marshall
-
Patent number: 8513981Abstract: A circuit for detecting out-of-band signals is disclosed. In one embodiment, the circuit includes a first differential circuit configured to level shift and positively rectify a differential input signal to produce a first output component of a differential output signal. The first differential circuit is further configured to generate and provide a common mode voltage of the differential input signal as a second component of the differential output signal. The circuit further includes a second differential circuit configured to level shift and output first and second fixed voltages based on an input reference voltage and a ground voltage. The circuit is configured to provide the differential output signal and the first and second fixed voltages to an indicator circuit configured to assert an indication responsive to detecting that a differential voltage of the differential output signal is greater than a differential voltage of the first and second fixed voltages.Type: GrantFiled: December 12, 2011Date of Patent: August 20, 2013Assignee: Advanced Micro DevicesInventors: Xin Liu, Arvind Bomdica
-
Patent number: 8513980Abstract: An apparatus is provided. The apparatus comprises backend circuitry and pairs of redundant input circuits. Each pair of redundant input circuits is configured to form a differential pair of transistors, and each redundant input circuit includes a multiplexer and a set of transistors. The multiplexer is coupled to the backend circuitry, and each transistor from the set of transistors has a first passive electrode, a second passive electrode, and a control electrode. The first passive electrode of each transistor from the set of transistors is coupled to the multiplexer, and the control electrodes from the set of transistors are coupled together.Type: GrantFiled: October 25, 2011Date of Patent: August 20, 2013Assignee: Texas Instruments IncorporatedInventors: Robert F. Payne, Baher S. Haroun
-
Patent number: 8502565Abstract: A buffer for converting sinusoidal waves to square waves with reduced phase noise is described herein. The buffer shunts current from the outputs of a differential amplifier during sinusoidal state transition periods at the differential amplifier inputs to increase the finite slope of square wave transition periods of the output square wave. More particularly, a sinusoidal wave having alternating peaks and valleys connected by sinusoidal state transition periods is applied to differential inputs of a differential amplifier to generate a square wave at the differential outputs, where the output square wave comprises alternating high and low states connected by square wave state transition periods having a finite slope. The output square wave is shaped to increase the finite slope of the square wave transition periods by providing additional paths between the differential outputs and ground that shunt current from the differential amplifier during the sinusoidal state transition periods.Type: GrantFiled: July 26, 2010Date of Patent: August 6, 2013Assignee: ST-Ericsson SAInventor: Torkel Arnborg